“All the opinion polls I’ve seen on the question on whether parliament should decide on the issue of same-sex marriage or the people via a plebiscite, show a very big majority in favour of a plebiscite,” he said.

“There’s no question it’s not the traditional way of resolving matters like this in Australia but this was the view taken by the Coalition party room – it was before I was prime minister. But nonetheless, it’s a view we are committed to and it is thoroughly democratic.

“And I can understand it is frustrating for those people who want to get on with it, and obviously it has a cost associated with it, that a parliamentary vote would not.”